ABSTRACT
Skilled motor behavior relies on the ability to control the body and to predict the sensory consequences of this control. While there is ample evidence that manual dexterity depends on handedness, it remains unclear whether control and prediction are similarly impacted. To address this issue, right-handed human participants performed two tasks either with the right or the left hand. In the first task, participants had to move a cursor with their hand so as to track a target that followed a quasi-random trajectory. This hand tracking task allowed testing the ability to control the hand along an imposed trajectory. In the second task, participants had to track with their eyes a target that was self-moved through voluntary hand motion. This eye tracking task allowed testing the ability to predict the visual consequences of hand movements. As expected, results showed that hand tracking was more accurate with the right hand than with the left hand. In contrast, eye tracking was similar in terms of spatial and temporal gaze attributes whether the target was moved by the right or the left hand. While these results extend previous evidence for different levels of control by the two hands, they show that the ability to predict the visual consequences of self-generated actions does not depend on handedness. We propose that the greater dexterity exhibited by the dominant hand in many motor tasks stems from advantages in control, not in prediction. Finally these findings support the notion that prediction and control are distinct processes.
SIGNIFICANCE STATEMENT Humans often exhibit greater manual dexterity with the dominant hand. Here we assessed whether handedness similarly impacts control and prediction, two key processes for skilled motor behavior. Using two eye-hand coordination tasks that differently rely on control and prediction, we show that, even though handedness impacts the accuracy of hand movement control, it has virtually no influence on the ability to predict the visual consequences of hand movements. We propose that the superior performance of the dominant hand stems from advantages in control, not in prediction. In addition, these findings provide further evidence that prediction and control are distinct neural processes.
Footnotes
Conflict of interest: Authors report no conflict of interest.
This work was part of Innovative Training Network 'Perception and Action in Complex Environment' (PACE) that has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement N° 642961. This paper reflects only the authors’ view and that the Research Executive Agency (REA) of the European Commission is not responsible for any use that may be made of the information it contains.
This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license, which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
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